Method and apparatus for sealing a closure to a can body

ABSTRACT

A method and apparatus for double seaming a can end closure to a can body by the application of a linearly movable force applying means to simultaneously apply vertical and horizontal forces tangentially to the curled end of a rim of the closure positioned on the open flanged end of the container. The chuck wall of the cover is held to restrain the latter and the container body against inboard bending during the application of the simultaneously applied forces. The simultaneously applied vertical and horizontal forces are applied to the rim progressively downwardly and inwardly relative to the container wall to further bend the rim and the underlying flanged end. During the progressive bending the rim curled end is restrained against downward movement to retain the free edge thereof facing generally inwardly and upwardly. The downward restraining of the rim is discontinued when the free end is in close proximity to the container wall. The flange end at the same time is bent downwardly to form a hook and clinched by the rim whereupon the application of a horizontal squeezing force folds the rim and clinched hook to form a double seam.

arly

ertig during ces. The

y rela- Primary Examiner-Lowell A. Larson A ttorneysFred P. Kostka, Joseph E. Kerwin and William A.

Dittman hm ABSTRACT: A method and apparatus for double seamin can end closure to a can body by the application of a line movable force applying means to simultaneously apply v cal and horizontal forces tangentially to the curled end of a rim of the closure positioned on the open flanged end of the container. The chuck wall of the cover is held to restrain the latter and the container body against inboard bendin the application of the simultaneously applied for simultaneously applied vertical and horizontal forces are a plied to the rim progressively downwardly and inwardl tive to the container wall to further bend the rim and the underlying flanged end. During the progressive bendin Henry E. Frankenberg Berwyn,lll.

[21] AppLNo. 744,963

[22] Filed United States Patent [45] Patented Jan. 19, 1M1

[73] Assignee [54] METHOD AND APPARATUS FOR SEALING A g the rim t to retain y and upwardly.

iscontinued when the free end is in close proximity to the container wall. The flange curled end is restrained against downward movemen the free edge thereof facing generally inwardl The downward restraining of the rim is d end at the same time is bent downwardly to form a hook and clinched by the rim whereupon the application of a horizontal squeezing force folds the rim and clinched hook to form a double seam.

04 2 00 moa mm t \U\ F W mw Ml 5111: 4 vi 2 1 a w B Q 3 "n 3 7 .2 S u" 4. TwI m T mm 2 3 m N W" n E "L m T mm MM w m C mfl m E m QT. .3 m A m N 8 n 8 .bn mmm. E m mum mm uww "us f. l. d i em UIF 7 9 111 1 mm new. n 5,0, ..l.|:l. .l. 3

PATENT EU JAN 1 9 Ian SHEET 1 [1F 2 IN VENTOR HENRY E. FRANKENBERG MM ATT'Y.

INVENTOR HENRY E. FRANKENBERG ATT'Y.

METHOD AND APPARATUS FOR SEALING A CLOSURE TO A CAN BODY The present invention relates to a method and apparatus for sealing end closures to container bodies and, more particularly, to a new and improved method and apparatus for forming a double seam to seal the end closure to the open end of the container body.

Heretofore, it has been common practice to double seam an end closure to a container body by means of rotating and rolling members. This prior apparatus employing the rolling and rotating members is embodied in equipment which is inherently complexand relatively expensive to manufacture. Moreover, the rotating and rolling means used to form the seam required a specified time period, which limited the production rate at which the covers are sealed to the container bodies.

It is the principal object of the present invention to provide a new and improved method for double seaming end closures to container bodies by using solely linear-reciprocating movement and thereby to reduce the time period required to perform the double seaming operation.

It is a further object to provide a new and improved apparatus for carrying out the method set forth in the immediately foregoing object.

IN THE DRAWINGS FIG. 1 is a sectional view of a can'closing machine embodying the principles of the present invention, showing on the right side of the centerline the components of the machine in an intermediate position during the formation of the double seam, and on the left side of the centerline in a position upon completing the formationdf the double seam; and

FIGS. 26 are fragmentary sectional views showing the relative positions of the machine components and the end closure rim and the can flange during the formation of the double seam. I

Referring now to the drawings, there is; shown a closing machine in which there is a container or can body 11 and a cover or end closure 12. The container body 11 may be of generally circular cross section having a sidewall 13 and a base or bottom closure 14. At the open end 15 the can body 11 is formed with an outwardly flared flange I6 which serves to form a hooked leg of a double seam 17. The flange 16 may be curved slightly downwardly as shown in FIG. 2.

The end closure 12 is of substantially standard construction comprising a central panel 18 along the outer end of which there is formed a rim 19. The rim I9 is turned in embracing relationship about the container flange 16 to form the double seam 17 for sealing the closure 12 to the container body 11. The rim 19 includes an inner chuck wall 21 which is seatable within the open end 15 of'the container body 11. Radially projecting outwardly fromthe chuck wall 21 is a curled end 22 which may be joined thereto by a web 23.

Prior to forming the double seam 17 the end closure 12 is delivered to the container open end and seated therein with the chuck wall 21 nesting within the container sidewall 13. In this position the curled end 22 lies outboard of the terminal end24 of the flange l6 and overlies the latter.

The closing machine 10 which may be used in practicing the method of the present invention comprises generally a base assembly 25 for supportingthe container 11 with the closure plate 12 seated or nested thereon and a vertically movable hollow forming or sealinghead assembly 26for forming the double seam 17. The closingmachine 10 is symmetrical about the longitudinal centerline and, for thepurposes of explanation, the machine as illustrated in FIG. Lshows the components thereof on the right side in an intermediate position during theformation of the double seam '17 and on the left side in a position after the doubleseam 17 has been completely formed. The fully open or initial startingposition is illus trated in phantom lines on the right of the centerline.

The base assembly 25 includes a base plate 27 to which there is fastened a housing 28 having a guiding opening 29 for guiding the forming head assembly 26. Disposed within the housing 28 is a cylindrical or guide sleeve 30 which receives the container body 11. Formed in the base plate 27 is a recess 3! in which the container base 14 is disposed.

At the upper end the cylindrical sleeve 30 is formed with an annular shoulder 32 spaced downwardly from the upper edge 33. Formed between the shoulder 32 and upper edge 33 is an upper reduced cylindrical guide section 34 and a contiguous frustoconical section 36.

Slidably disposed over the reduced cylindrical guide section 34 and the frustoconical section 36 is a rim retaining ring 37 having an opening 35 formed with a cylindrical section 38 and a frustoconical section 39 complementary to the upper cylindrical guide section 34 and frustoconical guide section 36 respectively. The outer circumference 40 of the ring 37 is formed as a frustum of a cone which may have the same slope as the slope of the frustoconical section 36. The base diameter of the rim retaining ring 37 is greater than the base diameter of the frustoconical circumference 40 and defines a ledge 41 which is vertically spaced from the upper end 42 of the ring 37. The rim retaining ring 37 is biased upwardly with the ledge 41 engaging a shoulder 54 by means of spring-biased pins or plungers 55 slidablysupported in the guide sleeve 30. In this position the upper end 42 is disposed slightly above the upper end 33 of the guide sleeve 30, as shown in FIGS. 24.

The forming head assembly 26 includes a forming head 43 formed with a cavity 44. The cavity 44 is formed at its lower end to provide a frustoconical surface 45 having the same slope as the outer circumference 40 of the ring 37. Adjacent the upper end and contiguous with the frustoconical surface 45 there is formed an enlarged cylindrical surface 46.

Slidably disposed within the cavity 44 is a chuck 47 to the upper end of which there is affixed a guide pin 48 having a head 49 slidably received in an opening 50 of a boss 51 extending from the forming head 43. The boss 51 is suitable connected to an operating means (not shown) for moving the forming head 43 toward and away from the base assembly 25.

At the upper end of the forming head 43 there is provided an opening 52 which communicates with a suitable source of fluid pressure for moving the chuck 47 downwardly lengthwise in engagement with the top closure plate 12 seated on the container 11.

At the lower end the chuck 47 is formed as shown with a chuck wall engaging wall or retaining surface 53 which is seatable within the confines of the cover chuck wall 21 to limit inward movement thereof during the formation of the double seam 17.

In operation the can body 11 is inserted into the guide sleeve 30 so that the base 14 is seated within the recess 31 and the end closure plate 12 nested within the open end of container as shown in FIGS. 1 and 2. To insert the container or can body 11, the base assembly 25 may be of split construction or, alternatively the forming head assembly 26 may be sufficiently vertically spaced from the base assembly 25 to permit insertion through the sleeve opening 29. The forming head assembly 26 is then actuated downwardly. During the downward movement thereof fluid pressure is applied through the opening 50 to move the chuck downwardly within the cavity 44 to hold the end closure 12 firmly clamped against the container 11. Thereafter, as shown in FIGS. 1 and 2, the forming head 43 is moved downwardly from the phantom line position so that the frustoconical surface 45 tangentially engages the curled end 22 of the closure plate rim 19. Such tangential engagement simultaneously applies a downward and inward force on the rim 19 and causes the terminal edge 56 of the curled end 22 to approach the upper end 42 of the rim retaining ring 37. The spring biasing force applied by the spring biased pins 55 acting upwardly on the rim retaining ring 37 resists downward movement thereof so that the curled end 22 is restrained against downward movement as shown in FIG.

Further downward movement of the forming head 43 causes further downward and inward movement of the curled end 22 along the top end of the rim retaining ring 37 to the position shown in FIG. 4.

It is to be noted that the frustoconical or tapered surface 45 continues to simultaneously apply a downward and inward force progressively on the rim 19 so that the underlying can flange 16 is also turned downwardly and inwardly. At the same time the force exerted tangentially on the rim 19 forces the chuck wall 21 into conformity with the retaining surface 53 on the chuck 47.

When the edge of the curled end 22 approaches the sidewall 13, the bottom end of the forming head 43 engages the ledge 41 on the rim retaining ring 37 whereby the latter is moved downwardly against the force of the spring biased plungers 55 toward the position in which the ledge 41 engages the shoulder 32 on the guide sleeve 30. During this movement the frustoconical surface 45 continues to bend the rim l9 and the underlying flange 16 inwardly toward the container body 11 into a substantially vertical attitude as shown in FIG. 5.

Further downward movement of the forming head 43 causes the cylindrical surface 46 to engage the rim l9 and apply a horizontal inward force to tightly force the latter and the underlying flange 16 into a flat vertical double fold or double seam 17 as shown in FIG. 6. During this period the upper end 33 of the guide sleeve is operative to force the rim 19 upwardly so that a tight double seam 17 is formed.

To remove the container 11 having the end closure 12 sealed thereon, the fluid pressure introduced into the cavity 44 to hold the chuck 47 in engagement with the end closure plate 12 is increased somewhat to permit relative movement of the forming head 43 and the chuck 47 so that the double seam 17 may be stripped from the cylindrical surface 46. After stripping. the pressure in the cavity 44 is further reduced to the original pressure and the forming head 43 and chuck 47 are simultaneously moved to the phantom position whereupon the closed container 11 may be removed from the apparatus.

lclaim:

l. A method for double seaming a container cover to a container body wherein said container body includes an outwardly flared flange projecting from the open end thereof and said container cover includes a rim having an upstanding chuck wall and terminating in a downwardly curled end, said method comprising positioning said container cover over said opening with said rim overlying said outwardly flared flange so that said curled end is spaced from the terminal end of said flange and said chuck wall is seated in said opening, applying a longitudinally movable force exerting member in a direction parallel to the longitudinal axis of the container to tangentially engage the curled end whereby simultaneous radial inwardly and downwardly directed forces bend said rim and said flange downwardly and inboard toward said container body, limiting downward movement of said curled end so that the latter assumes generally upturned position adjacent the container wall during the application of said radial inwardly and downwardly directed force, and continuing the application of said simultaneous radial force and vertical force progressively inwardly along said curled end and said bent portions of said horizontal web toward said container body until said rim clinches about said flange to form a double seam.

2. The method as defined in claim 1 comprising the step of supporting said chuck wall to restrain inward bending thereof as said forces are applied.

3. The method as defined in claim 2 wherein said simultaneous radial force and vertical force are continuously applied about the periphery of said rim.

4. The method as defined in claim 3 comprising the final step of applying solely a radially inwardly directed force to squeeze said double seam tightly against said container body.

5. A container sealing apparatus for double seaming an end closure to a can body wherein said can body includes an open end bounded by an outwardly flared flange and said end closure includes a chuck wallnestincgly disposed within said opening and a rim having a curled en said sealing means comprising a base assembly for supporting a can with said end closure seated in said open end, a forming head assembly longitudinally movable parallel to the longitudinal axis of said can, said forming head assembly including a chuck for holding said end closure on said can body and means for restraining radial inward displacement of said chuck wall, and forming head having tapering surface means tangentially engageable with said rim for simultaneously applying a horizontal and vertical force thereon so that said rim and underlying flange are progressively bent downwardly and radially inward and said curled end is turned upward to embrace said flange upon relative linear movement of said forming head assembly and said base assembly toward said other, and means restraining downward movement of said curled end so that the latter is turned upwardly to embrace said flange.

6. The invention as defined in claim 5 wherein said base assembly includes means restraining downward movement of said curled end so that the latter is turned upwardly to embrace said flange.

7. The invention as defined in claim 6 wherein said forming head includes a vertical surface means contiguous with said tapering surface means for squeezing said upwardly turned curled end and embracing said flange tightly against said container body to form a double seam.

8. The invention as defined in claim 7 wherein said chuck is mounted for lengthwise movement relative to said forming head. 

1. A method for double seaming a container cover to a container body wherein said container body includes an outwardly flared flange projecting from the open end thereof and said container coVer includes a rim having an upstanding chuck wall and terminating in a downwardly curled end, said method comprising positioning said container cover over said opening with said rim overlying said outwardly flared flange so that said curled end is spaced from the terminal end of said flange and said chuck wall is seated in said opening, applying a longitudinally movable force exerting member in a direction parallel to the longitudinal axis of the container to tangentially engage the curled end whereby simultaneous radial inwardly and downwardly directed forces bend said rim and said flange downwardly and inboard toward said container body, limiting downward movement of said curled end so that the latter assumes generally upturned position adjacent the container wall during the application of said radial inwardly and downwardly directed force, and continuing the application of said simultaneous radial force and vertical force progressively inwardly along said curled end and said bent portions of said horizontal web toward said container body until said rim clinches about said flange to form a double seam.
 2. The method as defined in claim 1 comprising the step of supporting said chuck wall to restrain inward bending thereof as said forces are applied.
 3. The method as defined in claim 2 wherein said simultaneous radial force and vertical force are continuously applied about the periphery of said rim.
 4. The method as defined in claim 3 comprising the final step of applying solely a radially inwardly directed force to squeeze said double seam tightly against said container body.
 5. A container sealing apparatus for double seaming an end closure to a can body wherein said can body includes an open end bounded by an outwardly flared flange and said end closure includes a chuck wall nestingly disposed within said opening and a rim having a curled end, said sealing means comprising a base assembly for supporting a can with said end closure seated in said open end, a forming head assembly longitudinally movable parallel to the longitudinal axis of said can, said forming head assembly including a chuck for holding said end closure on said can body and means for restraining radial inward displacement of said chuck wall, and forming head having tapering surface means tangentially engageable with said rim for simultaneously applying a horizontal and vertical force thereon so that said rim and underlying flange are progressively bent downwardly and radially inward and said curled end is turned upward to embrace said flange upon relative linear movement of said forming head assembly and said base assembly toward said other, and means restraining downward movement of said curled end so that the latter is turned upwardly to embrace said flange.
 6. The invention as defined in claim 5 wherein said base assembly includes means restraining downward movement of said curled end so that the latter is turned upwardly to embrace said flange.
 7. The invention as defined in claim 6 wherein said forming head includes a vertical surface means contiguous with said tapering surface means for squeezing said upwardly turned curled end and embracing said flange tightly against said container body to form a double seam.
 8. The invention as defined in claim 7 wherein said chuck is mounted for lengthwise movement relative to said forming head. 